Answer:
about 12 1/2 minutes
each mile he went to school took him 5 minutes and if his friend's house is 2 1/2 miles away then 2.5x5= 12.5
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Work Shown:
20 min = 20/60 = 1/3 of an hour
distance = rate*time
d = r*t
4 mi = (x mph)*(1/3 hr)
4 = x*(1/3)
4*3 = x
x = 12 mph
Damon's speed is 12 mph
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Now calculate the time it takes go travel to his friends house.
d = r*t
2.5 = 12*t
t = (2.5)/12
t = 25/120
t = (5*5)/(5*24)
t = 5/24
He takes 5/24 of an hour to go from school to Stefan's house.
Multiply by 60 to convert to minutes
(5/24)*60 = 12.5 minutes
